Treatment of cellulosic fibers with certain quaternary ammonium compounds



United States Patent 0.

3,510,246 TREATMENT OF CELLULOSIC FIBERS WITH CERTAIN QUATERNARY AM- MONIUM COMPOUNDS James L. Keen, New Brighton, and Lyle F. Elmquist, North St. Paul, Minn., assignors to General Mills, Inc., a corporation of Delaware No Drawing. Filed Feb. 8, 1967, Ser. No. 614,555 Int. Cl. D06m 13/34 US. Cl. 8116.2 13 Claims ABSTRACT OF THE DISCLOSURE Cellulosic fibers are treated with glycidyl quarternaries to improve the softness and/or water repellency thereof, said glycidyl quaternaries having the general formula The present invention relates to the process of treating cellulosic fibers with certain quaternary ammonium compounds and to the resulting treated fibers. More particularly, it relates to the method of improving the softness and/ or water repellency of cellulosic fibers by treating same with certain glycidyl quaternary ammonium compounds.

A number of fatty quaternary ammonium compounds have been used in the past for textile softening purposes. One such compound in use at the present time is dimethyl difatty quaternary ammonium chloride, in which the fatty group is predominantly a C saturated groupi.e. stearyl. While these compounds do soften textiles, particularly those derived from cellulosic fibers, such softening is far from permnaent and thus the said quaternaries are ordinarily added to the textiles at each washing. It would be highly desirable to eliminate the need to add softening agents each and every time the fabric is washed.

It is, therefore, an object of our invention to provide a process of treating cellulosic fibers to improve the softness and/ or water repellency thereof. It is a further object of the invention to provide a method of treating cellulosic fibers with certain glycidyl quaternary ammonium compounds. Another object of the invention is to provide cellulosic fibers of improved softness and/or water repellency. These and other objects will become apparent from the following detailed description.

We have now discovered that cellulosic fibers can be treated with certain glycidyl quaternary ammonium compounds to yield treated fibers with improved and relatively permanent softness and/or water repellency. We have also discovered that repeated washings of the treated fibers using well known and common commercially available anionic detergents generally further increases the softness and water resistance of the fibers. While we do not fully understand the latter discovery, it is believed that the anionic detergents complex in some way with the I quaternary ammonium moiety attached to the cellulose fibers. The quaternary ammonium compound is believed to be attached to the cellulose fibers mainly through ether linkages formed by the reaction of the epoxy group with hydroxyl groups of the cellulose.

The glycidyl quaternary ammonium compounds useful in the practice of the present invention have the followin idealized, general formula:

[R21+' R4C C H2]X Where R is an alkyl group of 1 to 4 carbon atoms, R is 3,510,246 Patented May 5, 1970 nonyl, decyl, decenyl, dodecyl, dodecenyl, ethyldodecyl,

tridecyl, hexadecyl, octadecyl, methyloctadecyl, octadecenyl and the like. Representative alkylene groups (R.,) are -CH -CH CH -CH CH CH and Representative anions (X are Cl-, Br, I, H50; and the like.

It is preferred that the alkyl group (R R is methyl, that the aliphatic hydrocarbon group (R R is a saturated, straight chained group of 12 to 24carb0n atoms, that the alkylene group (R is CH;; and that the anion -(X-) is Cl. It is also preferred that R is methyl. Compounds where R is an aliphatic hydrocarbon group of 8 to 24 carbon atoms are less preferred, mainly because they are somewhat more expensive due to the relatively low yields obtained in the preparation thereof. Also, as the chain length of R or R and R is reduced to below 12 carbon atoms, the ability of the glycidyl quaternaries to provide softness and/or water repellency is a so reduced somewhat. Thus compounds where R or R and R are aliphatic hydrocarbon groups of 8 to 11 carbon atoms are less preferred treating agents. However, when fibers treated with such shorter chain length compounds are washed in a solution of an anionic detergent, the softness and/or water repellency is generally increased as is also the case with the longer chain length glycidyl quaternaries. Apparently, the anionic detergent complexes with the quaternary moiety attached to the fibers and the resulting complex containing fibers have generally further improved softness and/ or water repellency.

The glycidyl quaternary ammonium compounds are prepared by reacting a tertiary amine with an epihalohydrin. Tertiary amines having the groups R R and R defined above may be employed. The epihalohydrin employed is one providing the group R defined above.

Representative tertiary amines are dimethylstearyl, dimethyldecyl, dimethyldodecyl, diethylstearyl, diethyldecyl, diethyldodecyl, dimethyloctyl, dimethyllauryl, dimethylmyristyl, dimethylpalmityl, dimethyloleyl, ,dimethyllinoleyl, dimethyltallow, dimethylhydrogenatedtallow, methyldioctyl, methyldioctenyl, ethyldioctyl, methyldidecyl, methyldidodecyl, ethyldidodecyl, methydihexadecyl, methyldilauryl, methyldimyristyl, methyldipalmityl, methyldioleyl, methyldilinoleyl, methyl di(hydrogenated tallow) and the like. A representative and preferred epihalohydrin is epichlorohydrin. The term tallow wherever used refers to the mixture of hydrocarbon radicals derived from the mixture of fatty acids obtained from tallow. The term hydrogenated tallow refers to such mixture of radicals which are essentially saturated and consist mainly of the stearyl and palmityl radicals.

The described glycidyl quaternary ammonium compounds are prepared by simply mixing substantially equimolar quantities of the tertiary amine and epihalohydrin in water and allowing the reaction to proceed preferably with agitation until formation of the product is complete. The water can be removed from the product by the use of a flash evaporator. It is also preferred to use a slight excess of the epihalohydrin (i.e. 5%). The reaction can be illustrated as follows using epichlorohydrin and dimethyldodecyl amine:

The preparation of the glycidyl quaternary ammonium compounds useful in the present invention is further illustrated by the fo lowing examples:

EXAMPLE A Four hundred twenty six grams (2 mole) dodecyldimethyl amine, 194 g. (2.1 mole) epichlorohydrin and 2000 g. water were added to a reaction flask. The reaction mixture was agitated at room temperature for about two hours and then the pH was adjusted to 10.4 with hydrochloric acid to stabilize the epoxy group. The reaction mixture was agitated overnight and then warmed to 45- 50 C. for two hours. It was then cooled to room temperature. The resulting product analyzed 23.1% by weight solids, the latter consisting of 81.8% by weight glycidyl quaternary of the formula Example A was repeated using 291 g. (1 mole) hydrogenatedtallowdimethyl amine, 97 g. (1.05 mole) epichlorohydrin and 100 g. water. The resulting product analyzed 27.4% by weight solids, the latter consisting of 86.5% bv weight glycidyl quaternary having the formula where R is hydrogenated tallow.

The glycidyl quaternary ammonium compounds are useful in treating cellulosic fibers or articles prepared from such fibers alone or in combination with noncellulosic fibers such as nylon, polyester fibers and the like. The invention is particularly applicable to the treatment of woven cellulosic textile materials. However, fibrous sheets, pads, films and the like, laid down from cellulose fibers can be treated even though in a non-woven form.

The cellulosic fibers can be treated with the glycidyl quaternary ammonium compound by various methods. A preferred method is to immerse the fibers or articles (i.e. fabrics) derived therefrom in an aqueous solution or emulsion of the glycidyl quaternary ammonium compound. The saturated fibers or articles are then dried and cured at temperatures in the range of about 90 C. to about 140 C. Curing temperatures of 100 C. to 110 C. are preferred. The reaction between the cellulosic fibers and the glycidyl quaternary ammonium compound is also preferably carried out in the presence of a catalyst. The catalyst may be an acid or base. Representative acid type catalysts are zinc perchlorate and zinc fiuoroborate. A preferred basic catalyst is sodium hydroxide. The' catalyst can be added to the fiber, the aqueous treating solution or after the glycidyl quaternary ammonium compound has been brought into contact with the fiber. One preferred method is to pretreat the fibers with an aqueous solution of NaOH. Another preferred procedure is to add the NaOH to the aqueous solution or emulsion of the glycidyl quaternary ammonium compound and then immerse the fibers in such composite treating solution. The catalyst can be used in widely varying amounts such as from about 0.01 to 15% by weight and higher based on the dry weight of the cellulosic fibers or articles derived therefrom. When NaOH is used, the concentration thereof in the aqueous solution should not exceed about 15% by weight. Also, such fairly concentrated solutions are preferably used to pretreat the fibers-i.e. the NaOH is added to the fibers prior to the addition of the glycidyl quaternary ammonium compound. The use of aqueous solutions or emulsions of the glycidyl quaternary ammonium compound are preferred in order to obtain a fairly even distribution of the said compound on the fibers or articles. In addition, the water is readily removed by drying, such as during the curing step.

The glycidyl quaternary ammonium compounds are used in an amount sufficient to improve the softness and/ or water repellency of the cellulosic fibers. Preferably, the compounds are used in an amount of about 0.05 to 10% by weight based on the dry weight of the fibers. Amounts of about 0.5 to 2.5% by weight are especially preferred. At the higher levels, the fibers have increased softness but greatly increased water repellency. At the lower levels, the fibers have increased softness and a considerable amount of water repellency.

As indicated above, washing of the treated cellulose fibers in aqueous solutions of anionic detergents tends to increase both softness and water repellency. It is believed that this is due to the formation of a complex between the anionic detergent and cationic moiety of the quaternary compound.

The following specific description further illustrates the present invention.

EXAMPLE 1 The glycidyl quaternaries as prepared in Examples A and B and Aliquat H226 (a dimethyl difatty quaternary ammonium chloride wherein the fatty groups are mainly stearyl) were each dissolved in 0.5% by weight aqueous NaOH solutions at a level of 1% by Weight. Birdseye cotton swatches (36 by 12") were immersed in an excess of treating solutions with agitation for one minute at room temperature and then wrung out to a by weight wet pickup based on the dry weight of the cloth. The swatches were then dried and cured 15 minutes at 100 C. Following this curing step, the swatches were rinsed in water to remove NaOH and again dried. The specimens of cotton thus treated were then subjected, along with an untreated control, to a softness test by a panel of women. The treated cloth and the control were placed in normal 8-pound wash loads and washed using water at F. and either Fels soap or Tide detergent at the recommended levels of usage. The samples were also coded prior to being subjected to the panel. The numbers in the following table indicate the number of times the indicated sample of each pair was chosen as being softer out of 24 tests. The smaller numbers in parenthesis indicate the statistical significance level of the test (the smaller the number, the more highly significant the result--N.S. means not significant).

1 A =cloth treated with the glycidyl quaternary ammonium compound of Example A; B =eloth treated with the glycidyl quaternary ammonium gomtpoiuradtgf Example B; C=cloth treated with Aliquat H226; D=unrea e e 0 The above data show that cotton fabric treated with the glycidyl quaternaries is very significantly softened. In addition it shows that the treatment according to the pres cut invention is generally more permanent than treatment with the well known softener Aliquat H226.

EXAMPLE 2 Swatches of Birdseye cotton cloth were treated as in Example 1 with the glycidyl quaternary ammonium compounds of Examples A and B and Aliquat H226. Additional swatches were pretreated in approximately by weight NaOH aqueous solutions for five minutes at room temperature followed by wringing out to about 200% Wet pickup based on the dry weight of the cloth. These pretreated swatches were then immersed in solutions of the glycidyl quaternaries of Examples A and B and cured as in Example 1. The various switches were then tested for water absorption before washing and after washing as in Example 1. In the following table, the figures represent the percent of water absorbed based on the amount of water absorbed by a pre-washed control, washed once in a non-ionic detergent. The lower the value, the more repellent the sample is.

ACloth treated with the glycidyl quaternary of Example A as in Example 1; B-Cloth treated with the glycidyl quaternary of Example B as in Example 1; A-Pre.-Cloth treated with the glycidyl quaternary of Example A using the NaOH pretreatment; B-Pre.Cloth treated with the glycidyl quaternary of Example B using the NaOH pretreatment.

2 Not tested.

The data of this example show that the glycidyl quaternaries improve the water repellency of the cotton cloth and that such improvement is generally heightened by washing of the cloth in anionic detergent solutions. The glycidyl quaternaries also generally give more permanent water repellency to the cloth than the conventional and known Aliquat H226 softener.

While specific examples of the invention have been described, it will be evident that other variations of the invention are possible within the scope of the following claims.

The embodiments of the invention in which an exclusive property or privilege is claimed are defined as follows:

1. A process of treating cellulosic fibers which comprises contacting said fibers with a glycidyl quaternary ammonium compound in an amount sufficient to improve the softness and/or water repellency of the fibers and curing the fibers, said glycidyl quaternary ammonium compound having the formula:

| m-r i-arofi omlm where R is an alkyl group of 1 to 4 carbon atoms, R is an alkyl group of 1 to 4 carbon atoms or an aliphatic hydrocarbon group of from 8 to 24 carbon atoms, R is an aliphatic hydrocarbon group of from 8 to 24 carbon atoms, R, is an alkylene group of 1 to 3 carbon atoms, and X- is an anion.

2. The process of claim 1 wherein the cellulosic fibers are in the form of a woven fabric.

3. The process of claim 1 wherein the cellulosic fibers are contacted with the glycidyl quaternary ammonium compound by immersing the former in an aqueous solution or emulsion of the latter.

4. The process of claim 1 wherein the glycidyl quaternary ammonium compound is used in an amount of about 0.05 to 10% by weight based on the dry weight of the cellulosic fibers.

5. The process of claim 1 wherein the curing of the fiber-glycidyl quaternary ammonium compound combination is carried out at temperatures of about C. to C.

6. The process of claim 1 wherein R is an alkyl group of 1 to 4 carbon atoms.

7. The process of claim 1 wherein R is an aliphatic hydrocarbon group of 12 to 24 carbon atoms.

8. The process of claim 1 wherein R is methyl, R is mehtyl, R is a saturated, straight chain hydrocarbon group of 12 to 24 carbon atoms, R, is CH; and X is 01-.

9. The process of claim 8 wherein R is dodecyl.

10. The process of claim 1 wherein the cellulosic fibers are in the form of a woven fabric, the contacting is carried out by immersing the fabric in an aqueous solution of the glycidyl quaternary ammonium compound, the aqueous solution contains a catalyst, the glycidyl quaternary ammonium compound is used in an amount of about 0.05 to 10% by weight based on the dry weight of the fabric, the curing is carried out at a temperature of about 90 C. to 140 C., and R is an alkyl group of 1 to 4 carbon atoms.

11. The process of claim 10 wherein the catalyst is sodium hydroxide, R and R are methyl, R is dodecyl, R is CH and X- is Cl.

12. The treated cellulosic fibers prepared by the process of claim 1.

13. The process of claim 1 including the step of treating the cellulosic fibers with an aqueous solution of sodium hydroxide prior to contacting the fibers with the glycidyl quaternary ammonium compound.

References Cited UNITED STATES PATENTS 9/1938 Schlack 8116.2 8/1941 Schirm 81 16.2

OTHER REFERENCES GEORGE F. LESMES, Primary Examiner J. R. MILLER, Assistant Examiner US. Cl. X.R. 26()348, 567.6

@2253?) UNITED STATES PATENT OFFICE CERTIFICATE OF CORRECTION Patent No. 3,510, 2 46 Dated May 5, 1970 Invencofls) James L. Keen and Lyle F. Elmquist It is certified that error appears in the above-identified patent and that said Letters Patent are hereby corrected as shown below:

Column 2, line t, "hydrcar'bon" should read --hydrocarbon--. Column 3, line 39 of the formula "[CH should read [611 Column 6, line 2 mehtyl" should read --methyl--.

mam mp;

3min JAMES 197! Must:

mm M. Fletc Mn; Officer dominion at Patonts 

